The present invention relates to Cucumber Vein Yellowing Virus (CVYV) resistant cucumber plants (Cucumis sativus L.), methods for providing Cucumber Vein Yellowing Virus (CVYV) resistant cucumber plants (Cucumis sativus L.), molecular markers for use in the method, and plants, plant parts, tissues, cells and/or seeds derived from, or originating from, the present Cucumber Vein Yellowing Virus (CVYV) resistant cucumber plants (Cucumis sativus L.).
Cucumber plants, i.e., plants of the botanical species Cucumis sativus, belong to the gourd family of Cucurbitaceae, also comprising family members like melons and squash. The edible fruits of the plant are generally designated as cucumbers.
Cucumbers usually are cylindrical, green skinned fruits, comprising approximately 96% water. The cucumber plant, also designated as Cucumis sativus L., which has been cultivated since long, is an important horticultural crop worldwide. Cucumbers are commonly harvested in an unripe stadium and may be used for the pickle industry or the fresh market.
Cucumber Vein Yellowing Virus, also abbreviated as CVYV, belongs to the Ipomovirus genus of the family of the Potyviridae. It is a rather unstable virus with rod-shaped particles, generally being 740-800 nm long and 15-18 nm wide. The viral nucleic acid of CVYV has been reported to consist of double stranded RNA.
The virus has a narrow host range that is mainly restricted to plants of the family of Cucurbitaceae. This family includes economic important crops like cucumbers, squashes (including pumpkins), melons and watermelons. Although CVYV infections generally are a major problem in cucumber production, also squash, zucchini, watermelon and melon productions are affected.
CVYV is generally transmitted by the whitefly Bremisia tabaci. CVYV infected plants generally show vein yellowing or vein clearing and stunting with corresponding yield reduction. CVYV infection may also cause death of the plants.
Thus, CVYV can have disastrous effects in crops when they become contaminated. Prevention of infection, by, for example, raising seedlings in a whitefly free environment, or treatment using, for example, pesticides, generally is costly and/or unfriendly to the environment. In addition, these methods do not always provide satisfactory results.
Cucumber Green Mottle Mosaic Virus, also abbreviated as CGMMV, is a RNA virus of the tobamovirus genus causing a severe disease of Cucurbits. Strains of CGMMV were first reported from the United Kingdom and Europe. The virus is present in all tissues and the virus is rapidly transmitted by workers hands, clothing, knives and other equipment and is additionally seed-borne. Heat treatment of seeds is commonly used to control viral contamination. CGMMV is also capable of spreading via surface water. Symptoms of yellowing, mottling and down-curling of the leaves have been reported though perhaps most significant are reports of moderate to severe fruit mottling and distortion. Such mottling and distortion of the fruits could quickly render infected crops unmarketable.
Cucumber Green Mottle Mosaic Virus is perhaps the most widespread and renowned of the tobamoviruses infecting cucumber crops. CGMMV is a worldwide problem in cucumber production areas like The Netherlands, Spain, Greece and India. Yield losses may be a much as 15%.
Cucumber Fruit Mottle Mosaic Virus, also abbreviated as CFMMV, is another family member of the tobamoviruses causing significant economic damage to cucumber plants (Cucumis sativus L). Symptoms of Cucumber Fruit Mottle Mosaic virus (CFMMV) infections are generally first recognized on fruits and apical leaves at a relatively advanced growth stage. Leaf symptoms include severe mosaic, vein banding and yellow mottling. In some cases, fully developed plants show severe wilting symptoms that lead to plant collapse. Rapid viral spread within greenhouses may lead to significant crop losses.
Considering the economic damages caused by Cucumber Vein Yellowing Virus(CVYV) in cucumber plants (Cucumis sativus L.), it is an object, amongst other objects, of the present invention to provide Cucumber Vein Yellowing Virus (CVYV) resistant cucumber plants (Cucumis sativus L.).
Further, it is an object, amongst other objects, of the present invention to provide methods and means for providing Cucumber Vein Yellowing Virus (CVYV) resistant cucumber plants (Cucumis sativus L.).